Rework documentation

[rubenvanerk]

Here's my shot at a new README. We might be able to get away with putting the documentation in here, but I'm not too sure.

Related: #498

[k00ni]

Thank you @rubenvanerk!

I took the liberty and made some changes in your branch. Hope it was OK. English is not my mother tongue so you might find instances to improve.

@Reqrefusion I moved a big chunk from the wiki into new documentation files.

Open/to discuss:

• Include new code from Make horizontal offset configurable #505?
• @Reqrefusion: Preparing a more detailed briefing for the config. I found this necessary because @rubenvanerk provides solutions to some problems by using the config feature. He had already made an addition in this direction on the wiki page. I also added a table. But still work in process. (source)
• Section with common problems?
• Section with known limitations?
• After PR got merged, adapt link in Using PdfParser without Composer #117

CC @likemusic

Is that the right direction?

[k00ni]

I refined some things and added latest wiki-content made by @Reqrefusion.

What is left to do here?

@Reqrefusion After this got accepted and merged I would like to remove all content from wiki and only leave a hint to our new documentation. That way there is no confusion where to find latest documentation. What do you think?

If there is anything I missed, please give me a hint.

[k00ni]

OK, I will leave this open until end of this week. If there are no objections or comments, this PR gets merged afterwards. Documentation is way from finished but with this work there is a good basement in my opinion, and we can continue with other PRs.

[Reqrefusion]

I feel bad seeing this so late. It seems like the end of Wiki has come. One of Github's nice but insufficient features. I will still make a few changes to the config. The current config is not very descriptive. The table I created beforehand makes trial and error easier.